<style type="text/css">
    .father {
        width: 100%;
        background: #ececdd;
        border: 1px solid #f9d7f7;
    }
  
    .son {
        height: 100px;
        width: 100%;
        margin-top: 50px;
        margin-bottom: 30px;
        background: #d3cff7;
    }
  </style>
  
  <div class="father">
      <div class="son">
          son
      </div>
  </div>